The advertising watchdog has criticised Virgin Media for misleading the public by running ads for its superfast broadband that used fine print that was so small it was impossible to read.

The national newspaper ad campaign, which featured Olympian and world record sprinter Usain Bolt, promoted Virgin Media's superfast broadband service with the strapline "Faster for a fiver".

Small print at the bottom of the press ad outlined various restrictions and terms and conditions running to more than 230 words in length.

The Advertising Standards Authority received a complaint that the print was not legible to a "normally-sighted" person, which meant that the ad was misleading.

Virgin Media said that it used a minimum font size of between 5.5 and 6 points for small print that is "clearly visible to a normally-sighted person".

It argued that the "industry standard" was for small print to be written in font size of 4 and 4.5 points, meaning that it had provided text "quite a bit larger than average".

The ASA said that the size of the text, hampered by not great quality printing, meant it was "not clearly visible to a normally-sighted person reading the marketing communication once, from a reasonable distance and at a reasonable speed".

"Because the small print was not presented clearly, and contained material information, we concluded that the ad was misleading," said the ASA, which banned it and told Virgin Media to present its small print clearly in the future.

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